CVE-2026-74546

A flaw was found in the Linux kernel's hwmon (hardware monitoring) subsystem, specifically within the adt7470 driver. A local attacker could exploit a time-of-check to time-of-use (TOCTOU) race condition. If fan data becomes zero between a validation check and a conversion operation, it can lead to a divide-by-zero error, causing a system crash and resulting in a Denial of Service (DoS).

A low-impact flaw was found in the Linux kernel's hwmon subsystem, in the adt7470 hardware monitoring driver. On systems where this driver and its supported hardware monitoring device are present, a local attacker could exploit a time-of-check to time-of-use (TOCTOU) race condition during fan speed reads: if the cached fan data changes to zero between the FAN_DATA_VALID() check and the FAN_PERIOD_TO_RPM() conversion, a divide-by-zero error occurs, crashing the kernel and causing a local denial of service. There is no impact to the confidentiality or integrity of the system.

Red Hat Enterprise Linux 10 (kernel, including the 10.0.z, 10.2.z, and 10.3 update streams) and Red Hat In-Vehicle OS 2 (kernel and kernel-ivos-qualcomm components) contain the affected code and are marked AFFECTED. The vulnerable code is not present in Red Hat Enterprise Linux 6, 7, 8, and 9, so those products are not affected.

For the affected products, the fix is currently deferred: given the low assessed impact, the fix will be delivered in a future update rather than through an immediate z-stream update. The residual risk is limited to a local denial of service (kernel crash) on systems using the adt7470 driver. While the assigned CVSS:3.1 base score is 5.5 (moderate), Red Hat Product Security rates the overall impact of this flaw as LOW because exploitation requires local access on a system with the adt7470 driver and its supported hardware present, and the result is limited to availability with no confidentiality or integrity impact.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.